Wikijunior:Bugs/Walking Stick
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[edit] What does it look like?
As its name suggests, the Walking Stick is an insect that looks like a stick or twig. Its color is usually brown or green, but may be grey or shades of red. Stripes, spots, and speckles are common.
The common American Walking Stick is slender and shiny with two long antennas. The adult male is 2 to 3 inches long with bands of color and curved appendages on its abdomen. The adult female is 3 to 4 inches long.
A Walking Stick looks like a stick or leaf as shown in the picture on the right. It will gently sway back and forth as if being blown by the wind. You can almost say it is a mini branch of a tree or plant. It will act just like one to prevent things from seeing it.
Stick insects do not fly very well, and most have no wings. Those that do have two pairs. Usually the front wings are small. The back ones are more important for flying. When they are not in use they are tucked away beside its body. They have the appearance of withered leaves.
[edit] Where does it live?
The best place to see stick insects in the wild is the tropics. That is the area nearest the equator where the climate is hot and sunny year round. Stick insects are abundant in the rainforest of Asia, Africa, and South America. They can also be found in North America, Australia, and warmer parts of Europe around the Mediterranean Sea.
The Walking Stick can be found on the stems of trees and bushes in forested and bushy areas. Its natural habitat is woodlands where broadleaf trees are abundant.
The common American Walking Stick can be found east of the Mississippi River from southern Canada to central Florida. It is also found in parts of Arizona and northern Mexico.
[edit] What does it eat?
Most are herbivorous and eat plants and leaves. They eat plants like blackberry vines, oak leaves and rose bushes.
An adult American Walking Stick prefers to eat oak leaves. In the early part of its life (the nymph stage) it feeds on oak leaves, but also on various plants and shrubs under the oaks.
[edit] How does it defend itself?
When soldiers go into battle, they are often camouflaged or hidden from their enemies by the patchy colors on their uniforms. The camouflage they wear allows them to blend into their surroundings.
The Walking Stick also uses disguise to hide from predators. The surrounding vegetation makes it almost invisible. A stick insect can also remain almost still for hours at a time, looking exactly like a plant’s stem. It will gently sway back and forth as if being blown by the wind and might be mistaken for a small branch.
Sometimes the undersides of the wings are brightly colored. If attacked, it will open its wings very fast to reveal a bright flash of color that may scare the predator away.
Often, instead of being used for flight, the wings act as miniature parachutes. If threatened, the stick insect falls from the branch, unfolds its wings and glides to safety.
Some can give off an unpleasant odor to repel predators. Some have sharp spines that act like a needle and when a predator comes to close, it gets pricked!
[edit] What stages of metamorphosis does it go through?
About two weeks after mating, the female stick insect lays her egg. She deposits them through a special tube at the tip of her abdomen called an ovipositor.
Many types of stick insects simply drop the eggs on the ground, but some species take more care to protect them. Some are buried in the ground or hidden in the bark of a tree. Some are even attached to leaves or branches by a special sticky substance.
A few species have a more impressive method of laying eggs. The female hangs upside down from a branch and arches her abdomen. Then she straightens up and flicks the eggs away. The eggs are thrown some distance scattered over a wide area. They hatch in the spring by emerging from a tiny cap, or lid at one end of the egg.
The Walking Stick starts off as a tiny black round egg laid by an adult female Walking Stick. When the egg first hatches it is referred to as a nymph. A nymph looks like a mini Walking Stick. It may be lighter in color.
To grow bigger the nymph molts, which means it grows a new skeleton underneath the old one. Then the old skin cracks open and the insect emerges with a brand new cover. The new outer casing is soft at first, and the insect must be careful to avoid danger until it hardens.
Finally, after several molts, it becomes an adult Walking Stick which can reproduce again. The average lifespan of a Walking Stick is one to two years after hatching.
[edit] What special behavior does it exhibit?
It can adapt to its surroundings to look just like a twig or a leaf. It is a nocturnal insect, which means it just sits the whole day and eats at night. It has claws and suction pads on its feet that enable it to climb. As a nymph grows it molts. That is, it gets out of its old skin and grows a bigger one!
A young stick insect has the special ability to regenerate or regrow a lost leg when it molts. Imagine being able to regrow a lost arm or leg! A young stick insect can lose a healthy leg in order to escape a predator. Each time it molts, the lost limb will gradually grow back. After three or four molts the lost limb will have completely grown back, but it will be slightly shorter than the original.
A peculiar thing happens when an antenna is lost. Instead of growing a new antenna, the stick insect will grow a new leg in its place. Adult stick insects no longer molt, so only nymphs can replace body parts in this way.
[edit] How does this bug affect people?
Walking Sticks do not seem to have a great impact on humans. There may be problems when they are brought to areas where they do not belong naturally. Some people even keep them as pets!
Common American Walking Sticks are sometimes thought of as pests because large numbers feeding at once can eat most of the leaves on a tree.
Another species, the Indian Walking Stick, is native to Madagascar. Captive colonies are often kept on hedges. The Indian Walking Stick is often used as a study animal by scientists.
